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Story highlights

The endorsement from South Carolina Gov. Nikki Haley was important to Rubio's performance in the state but it wasn't the only key

Rubio's campaign packed his schedule with even more events -- and opened access to the media in the days leading up to the primary

(CNN) —  

Marco Rubio’s rebound here in South Carolina was more than just Gov. Nikki Haley’s endorsement.

It was rooted in years of methodical planning, building inroads with the state’s political power players, developing a deep network of donors stemming from his 2010 Senate race and hiring well-connected South Carolina-bred operatives who had circled February 20 on the calendar as a possible turning point in the race.

And the campaign benefited from a subtle reboot – including more press access and less debate prep – after Rubio’s disastrous showing in New Hampshire nearly torpedoed his campaign.

In essence, Rubio wanted to show his personal side after being lampooned as a scripted and robotic candidate following his run-in with New Jersey Gov. Chris Christie in New Hampshire.

But he also wanted to recapture the energy that propelled him to a better-than-expected finish in Iowa, something his team worked behind-the-scenes to ensure after his well-regarded performance in last week’s South Carolina debate.

“I think Marco came in with the reality that Marco just needed to be Marco – not try to outperform or overperform, but just be himself,” said South Carolina Sen. Tim Scott, who had grown close to Rubio over the years, including when the two attended Scott’s church just outside of Charleston a couple years back.

Rubio’s virtual tie for second with Ted Cruz now reorders the GOP race and gives him a serious shot at emerging as the alternative to Donald Trump now that Jeb Bush is out of the race. He now hopes that a strong showing in Nevada will propel him to stay in the top tier ahead of Super Tuesday on March 1 as he competes with another foe – Ohio Gov. John Kasich – for moderate GOP voters, including with a trip next week to Michigan where Kasich is investing heavily.

“I give us the best chance to unify,” Rubio said Sunday in an interview with CNN’s Jake Tapper on “State of the Union.”

“Who do the Democrats fear most? Who do they not want to run against? I think everyone now acknowledges that’s me,” he said. “We’ve got to bring the Republican Party together. We’re not gonna win – we’re not going to beat Hillary Clinton or Bernie Sanders – if we’re still divided in September or October.”

RELATED: Donald Trump, Hillary Clinton win big; Jeb Bush drops out

What gave Rubio a late boost was Haley’s endorsement this week, which both Rubio, Bush and Texas Sen. Ted Cruz had heavily sought. Rubio had met with Haley once, but rumors about the popular governor potentially backing the senator had persisted for weeks. It was not locked down until the day it became public, a sign that his momentum was growing.

The campaign cut an ad promoting Haley’s endorsement within hours of her decision, blanketing the state with her endorsement.

Turning points

While Haley’s announcement was important, it was not central to turning the race around in South Carolina, according to top Rubio advisers. (A Rubio adviser later stressed the importance of her endorsement, saying it was crucial to the second-place finish.)

To turn around his poor performance in New Hampshire, Rubio and his team calculated that first they had to sell voters and the media that the momentum was really behind him.

One way to do that: Big crowds.

After a mistake-free debate, where he drew praise from the media and took a veiled swipe at Donald Trump by defending George W. Bush, Rubio sought to capitalize on that performance by holding a major rally the next day.

So Rubio’s team spent weeks aggressively promoting a rally in Easley, just a quick drive from Greenville, where the debate was held the night before.

Through social media and via word of mouth, including from a South Carolina state representative who represents the area, Rubio’s team attracted a crowd of more than 2,000 – something that generated positive news coverage and created a sense that Rubio had dramatically turned things around.

“What we have seen over the last 11 days is Marco’s momentum is real,” Scott said.

RELATED: 8 takeaways from South Carolina and Nevada

But even as Rubio was generating earned media through big crowds, his campaign packed his schedule with even more events – and opened access to the media. During his campaign trips in Iowa and New Hampshire, Rubio and his staff sheltered him from the traveling press corps, hand-selecting reporters to ask questions during short media availabilities and declining most follow-up questions.

After his New Hampshire loss, Rubio and his team immediately decided to let him loose. Rubio spent 45 minutes with the press in a free-flowing back-and-forth with reporters aboard his campaign plane to Greenville, South Carolina. He later had lunch twice with the traveling press corps and spent time on his bus answering questions from reporters.

His stump speeches were essentially the same as before. But his campaign projected a sense of ease, a sign that his team wanted to end the narrative that Rubio was unable to get beyond his talking points. In a sense, the mentality internally shifted to Rubio acting as a front-runner to a scrappy underdog, something they believed helped provide new energy to his campaign.

Moreover, debate prep became less intense, according to Rubio sources, something they believe ultimately helped the candidate.

“Marco is better when he’s an underdog,” one Rubio adviser said.

Connections to the state

Rubio’s success in South Carolina dates back to 2009, when he was running as a tea party insurgent in the 2010 midterms against then-Florida Gov. Charlie Crist, the then-Republican who later became a Democrat.

At the time, Crist froze out major Florida donors, preventing Rubio from raising money in the state.

So Rubio turned to his lone Senate endorser at the time, then-Sen. Jim DeMint of South Carolina, to hit up deep-pocketed donors in the Palmetto State – creating a network that he tapped into during his run for president.

Moreover, several top advisers either hail from South Carolina or have worked in politics here, including Terry Sullivan, Rubio’s campaign manger who has advised more than 100 federal and state races here.

Sullivan helped recruit Rep. Trey Gowdy to run for the House; and Gowdy was one of Rubio’s first high-profile endorsers. But Sullivan was hardly the only operative with deep South Carolina ties – even Rubio’s super PAC had hired Jon Lerner, a consultant with deep ties to Haley.

Haley’s endorsement generated the media buzz, but Scott and Gowdy were far more instrumental in using their political machines and connections to help propel Rubio to a solid finish, according to top operatives.

Gowdy and Scott spent the final 11 days of the campaign on the trail with Rubio, hitting 25 events.

As he spoke with several hundred supporters here in a raucous celebration, Rubio touted the three Republicans – and himself – as the new face for the Republican Party.

“Tonight here in South Carolina, the message is pretty clear,” Rubio said. “The country is now ready for a new generation of conservatives to guide us into the 21st century.”

CNN’s Eric Bradner contributed